مستخدم:ASEN6/ملعب37

من ويكيبيديا، الموسوعة الحرة
Chemical engineers design, construct and operate process plants (fractionating columns pictured).

الهندسة الكيميائية هي نوع معين من الهندسة التي تتعامل مع دراسة تشغيل وتصميم المصانع الكيميائية وكذلك طرق تحسين الإنتاج. يطور المهندسون الكيميائيون عمليات تجارية اقتصادية لتحويل المواد الخام إلى منتجات مفيدة. تستخدم الهندسة الكيميائية مبادئ الكيمياء والفيزياء والرياضيات والأحياء والاقتصاد لاستخدام الطاقة والمواد وإنتاجها وتصميمها ونقلها وتحويلها بكفاءة. يمكن أن يتراوح عمل المهندسين الكيميائيين من استخدام تقنية النانو والمواد النانوية في المختبر إلى العمليات الصناعية واسعة النطاق التي تحول المواد الكيميائية والمواد الخام والخلايا الحية والكائنات الحية الدقيقة والطاقة إلى أشكال ومنتجات مفيدة. يشارك المهندسون الكيميائيون في العديد من جوانب تصميم المصنع وتشغيله ، بما في ذلك تقييمات السلامة والمخاطر ، وتصميم العمليات وتحليلها ، والنمذجة ، وهندسة التحكم ، وهندسة التفاعلات الكيميائية ، والهندسة النووية ، والهندسة الحيوية ، ومواصفات البناء ، وتعليمات التشغيل.

عادة ما يحمل المهندسون الكيميائيون شهادة في الهندسة الكيميائية أو هندسة العمليات. قد يكون لدى المهندسين الممارسين شهادات مهنية وأن يكونوا أعضاء معتمدين في هيئة مهنية. وتشمل هذه الهيئات معهد المهندسين الكيميائيين (IChemE) أو المعهد الأمريكي للمهندسين الكيميائيين (AIChE). ترتبط درجة في الهندسة الكيميائية ارتباطًا مباشرًا بجميع التخصصات الهندسية الأخرى ، بدرجات مختلفة.

أصل الكلمة[عدل]

George E. Davis

A 1996 British Journal for the History of Science article cites James F. Donnelly for mentioning an 1839 reference to chemical engineering in relation to the production of sulfuric acid.[1] In the same paper, however, George E. Davis, an English consultant, was credited with having coined the term.[2] Davis also tried to found a Society of Chemical Engineering, but instead it was named the Society of Chemical Industry (1881), with Davis as its first secretary.[3][4] The History of Science in United States: An Encyclopedia puts the use of the term around 1890.[5] "Chemical engineering", describing the use of mechanical equipment in the chemical industry, became common vocabulary in England after 1850.[6] By 1910, the profession, "chemical engineer," was already in common use in Britain and the United States.[7]

التاريخ[عدل]

مفاهيم وابتكارات جديدة[عدل]

Demonstration model of a direct-methanol fuel cell. The actual fuel cell stack is the layered cube shape in the center of the image.

In 1940s, it became clear that unit operations alone were insufficient in developing chemical reactors. While the predominance of unit operations in chemical engineering courses in Britain and the United States continued until the 1960s, transport phenomena started to experience greater focus.[8] Along with other novel concepts, such as process systems engineering (PSE), a "second paradigm" was defined.[9][10] Transport phenomena gave an analytical approach to chemical engineering[11] while PSE focused on its synthetic elements, such as control system and process design.[12] Developments in chemical engineering before and after World War II were mainly incited by the petrochemical industry;[13] however, advances in other fields were made as well. Advancements in biochemical engineering in the 1940s, for example, found application in the pharmaceutical industry, and allowed for the mass production of various antibiotics, including penicillin and streptomycin.[14] Meanwhile, progress in polymer science in the 1950s paved way for the "age of plastics".[15]

Safety and hazard developments[عدل]

Concerns regarding the safety and environmental impact of large-scale chemical manufacturing facilities were also raised during this period. Silent Spring, published in 1962, alerted its readers to the harmful effects of DDT, a potent insecticide.[بحاجة لمصدر] The 1974 Flixborough disaster in the United Kingdom resulted in 28 deaths, as well as damage to a chemical plant and three nearby villages.[بحاجة لمصدر] The 1984 Bhopal disaster in India resulted in almost 4,000 deaths.[بحاجة لمصدر] These incidents, along with other incidents, affected the reputation of the trade as industrial safety and environmental protection were given more focus.[16] In response, the IChemE required safety to be part of every degree course that it accredited after 1982. By the 1970s, legislation and monitoring agencies were instituted in various countries, such as France, Germany, and the United States.[17]

Recent progress[عدل]

Advancements in computer science found applications designing and managing plants, simplifying calculations and drawings that previously had to be done manually. The completion of the Human Genome Project is also seen as a major development, not only advancing chemical engineering but genetic engineering and genomics as well.[18] Chemical engineering principles were used to produce DNA sequences in large quantities.[19]

المفاهيم[عدل]

قالب:Chemical engineering

Chemical engineering involves the application of several principles. Key concepts are presented below.

Plant design and construction[عدل]

Chemical engineering design concerns the creation of plans, specifications, and economic analyses for pilot plants, new plants, or plant modifications. Design engineers often work in a consulting role, designing plants to meet clients' needs. Design is limited by several factors, including funding, government regulations, and safety standards. These constraints dictate a plant's choice of process, materials, and equipment.[20]

Plant construction is coordinated by project engineers and project managers,[21] depending on the size of the investment. A chemical engineer may do the job of project engineer full-time or part of the time, which requires additional training and job skills or act as a consultant to the project group. In the USA the education of chemical engineering graduates from the Baccalaureate programs accredited by ABET do not usually stress project engineering education, which can be obtained by specialized training, as electives, or from graduate programs. Project engineering jobs are some of the largest employers for chemical engineers.[22]

Process design and analysis[عدل]

A unit operation is a physical step in an individual chemical engineering process. Unit operations (such as crystallization, filtration, drying and evaporation) are used to prepare reactants, purifying and separating its products, recycling unspent reactants, and controlling energy transfer in reactors.[23] On the other hand, a unit process is the chemical equivalent of a unit operation. Along with unit operations, unit processes constitute a process operation. Unit processes (such as nitration and oxidation) involve the conversion of materials by biochemical, thermochemical and other means. Chemical engineers responsible for these are called process engineers.[24]

Process design requires the definition of equipment types and sizes as well as how they are connected and the materials of construction. Details are often printed on a Process Flow Diagram which is used to control the capacity and reliability of a new or existing chemical factory.

Education for chemical engineers in the first college degree 3 or 4 years of study stresses the principles and practices of process design. The same skills are used in existing chemical plants to evaluate the efficiency and make recommendations for improvements.

Transport phenomena[عدل]

Modeling and analysis of transport phenomena is essential for many industrial applications. Transport phenomena involve fluid dynamics, heat transfer and mass transfer, which are governed mainly by momentum transfer, energy transfer and transport of chemical species, respectively. Models often involve separate considerations for macroscopic, microscopic and molecular level phenomena. Modeling of transport phenomena, therefore, requires an understanding of applied mathematics.[25]

التطبيقات والممارسة[عدل]

Two computer flat screens showing a plant process management application
يستخدم المهندسون الكيميائيون أجهزة الكمبيوتر للتحكم في الأنظمة الآلية في المصانع.[26]
المشغلون في مصنع كيميائي باستخدام لوحة تحكم تناظرية قديمة ، شوهدت في ألمانيا الشرقية ، 1986

المهندسون الكيميائيون "يطورون الطرق الاقتصادية لاستخدام المواد والطاقة".[27] يستخدم المهندسون الكيميائيون الكيمياء والهندسة لتحويل المواد الخام إلى منتجات قابلة للاستخدام ، مثل الأدوية والبتروكيماويات والبلاستيك على نطاق صناعي واسع النطاق. كما أنهم يشاركون في إدارة النفايات والبحث. يمكن للجانبين التطبيقي والبحثي الاستفادة بشكل مكثف من أجهزة الكمبيوتر.[26]

قد يشارك المهندسون الكيميائيون في أبحاث صناعية أو جامعية حيث يتم تكليفهم بتصميم وتنفيذ التجارب لإنشاء طرق أفضل وأكثر أمانًا للإنتاج ومكافحة التلوث والحفاظ على الموارد. قد يشاركون في تصميم وبناء المصانع كمهندس مشروع. يستخدم المهندسون الكيميائيون الذين يعملون كمهندسين للمشروع معرفتهم في اختيار أساليب الإنتاج المثلى ومعدات المصنع لتقليل التكاليف وزيادة السلامة والربحية إلى أقصى حد. بعد إنشاء المصنع ، قد يشارك مديرو مشاريع الهندسة الكيميائية في ترقيات المعدات واستكشاف الأخطاء وإصلاحها والعمليات اليومية إما بدوام كامل أو بأدوار استشارية.[28]

أنظر أيضاً[عدل]

Related topics[عدل]

المجالات والمفاهيم ذات الصلة[عدل]

هيئات مختصة[عدل]

المراجع[عدل]

  1. ^ Cohen 1996، صفحة 172.
  2. ^ Cohen 1996، صفحة 174.
  3. ^ Swindin، N. (1953). "George E. Davis memorial lecture". Transactions of the Institution of Chemical Engineers. ج. 31.
  4. ^ Flavell-While، Claudia (2012). "Chemical Engineers Who Changed the World: Meet the Daddy" (PDF). The Chemical Engineer. 52-54. مؤرشف من الأصل (PDF) في 2016-10-28. اطلع عليه بتاريخ 2016-10-27.
  5. ^ Reynolds 2001، صفحة 176.
  6. ^ Cohen 1996، صفحة 186.
  7. ^ Perkins 2003، صفحة 20.
  8. ^ Cohen 1996، صفحة 185.
  9. ^ Ogawa 2007، صفحة 2.
  10. ^ Perkins 2003، صفحة 29.
  11. ^ Perkins 2003، صفحة 30.
  12. ^ Perkins 2003، صفحة 31.
  13. ^ Reynolds 2001، صفحة 177.
  14. ^ Perkins 2003، صفحات 32–33.
  15. ^ Kim 2002، صفحة 7S.
  16. ^ Kim 2002، صفحة 8S.
  17. ^ Perkins 2003، صفحة 35.
  18. ^ Kim 2002، صفحة 9S.
  19. ^ American Institute of Chemical Engineers 2003a.
  20. ^ Towler & Sinnott 2008، صفحات 2–3.
  21. ^ Herbst, Andrew; Hans Verwijs (Oct. 19-22). "Project Engineering: Interdisciplinary Coordination and Overall Engineering Quality Control". Proc. of the Annual IAC conference of the American Society for Engineering Management 1 ((ردمك 9781618393616)): 15–21
  22. ^ "What Do Chemical Engineers Do?".
  23. ^ McCabe, Smith & Hariott 1993، صفحة 4.
  24. ^ Silla 2003، صفحات 8–9.
  25. ^ Bird, Stewart & Lightfoot 2002، صفحات 1–2.
  26. ^ أ ب Garner 2003، صفحات 47–48.
  27. ^ American Institute of Chemical Engineers 2003، Article III.
  28. ^ Garner 2003، صفحات 49–50.

Bibliography[عدل]

قالب:Chemical engg قالب:Engineering fields